CN105399067B - A kind of method for improving ketazine yield in ketazine process hydrazine hydrate still-process - Google Patents
A kind of method for improving ketazine yield in ketazine process hydrazine hydrate still-process Download PDFInfo
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- CN105399067B CN105399067B CN201510705783.8A CN201510705783A CN105399067B CN 105399067 B CN105399067 B CN 105399067B CN 201510705783 A CN201510705783 A CN 201510705783A CN 105399067 B CN105399067 B CN 105399067B
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- ketazine
- hydrazine hydrate
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B21/00—Nitrogen; Compounds thereof
- C01B21/082—Compounds containing nitrogen and non-metals and optionally metals
- C01B21/16—Hydrazine; Salts thereof
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C249/00—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton
- C07C249/16—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of hydrazones
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Abstract
The invention discloses a kind of method of the raising hydrazine hydrate yield in preparation of hydrazine hydrate by use of ketazine still-process.It after the by-product salt solution heat exchange after heat exchanger and destilling tower processing first by the reaction solution of synthetic reaction during ketazine process hydrazine hydrate production by being sent into destilling tower, and reacting liquid temperature is 90 110 DEG C after heat exchange；Then gas phase acetone is passed through between 5 15 blocks of column plates under input of column plate, the mass ratio of the acetone and reaction solution is 0.2 0.4；Hydrazine reaction generation ketazine is hydrated in gas phase acetone and reaction solution, react the light component ketazine of generation and the acetone of excess is separated by distilling from liquid, through recovered overhead, tower reactor hydrazine hydrate content is reduced, avoids the hydrazine hydrate of generation from draining with by-product salt solution, so as to improve hydrazine hydrate yield, hydrazine hydrate yield reaches more than 95%, hydrazine hydrate content is less than 1.5g/L in by-product brine, reduces the follow-up intractability of by-product brine, reduces the consumption for the treatment of agent.
Description
Technical field
The present invention relates to it is a kind of with ammonia, sodium hypochlorite, acetone be raw material generation hydrazine hydrate during improve yield method,
More specifically, it is a kind of method of raising ketazine yield in still-process.
Background technology
Hydrazine hydrate, also known as：Hydrazine hydrate, chemical formula N2H4·H2O, it is strong reductant, is important industrial chemicals,
It is the raw material of medicine, agricultural chemicals, dyestuff, foaming agent, developer, antioxidant；Deoxygenated for boiler water, high pure metal is produced, is had
Machine compound synthesis and reduction, rare element separation, also serve as the manufacture of rocket fuel and explosive, with advances in technology, society
Can development, in recent years the application field of hydrazine hydrate constantly widening.The production method of hydrazine hydrate mainly has Raschig process, urea
Method, ketazine process, peroxide passivation and air oxidation process etc..The hydrazine hydrate production method that the present invention mentions is ketazine process, it
It is using acetone, sodium hypochlorite and ammonia reaction production intermediate-ketazine, ketazine hydrolysis production hydrazine hydrate.Its primary chemical
Reaction equation is：
2NaOH+Cl2→NaCl+NaClO+H2O
NH3+NaClO→NH2Cl+NaOH
2CH3COCH3+NH3+NH2Cl+NaOH→(CH3)2C=N-N=(CH3)2C+3H2O+NaCl
(CH3)2C=N-N=C (CH3)2+3H2O→N2H4·H2O+2CH3COCH3
It can be seen that, to be produced during the synthetically produced ketazine of ammonia, acetone, sodium hypochlorite from above-mentioned chemical reaction
Sodium chloride, while raw material sodium hypochlorite will bring a certain amount of sodium chloride into, because sodium chloride is all dissolved in material body in reaction solution
In system, to carry out in the prior art separate most efficient method be to be separated by heating rectifying, in reaction excessive acetone and
The light component such as ammonia and part water and ketazine respectively enters ammonia from distillation tower top and acetone recovery system is handled, and ketazine is gone
Hydrolysis, and bottom of towe sodium chloride-containing salt solution then discharges carry out otherwise processed.
Because with the presence of substantial amounts of water, the condition such as temperature, pressure is similar with hydrolysis device simultaneously in still-process, this
Under the conditions of ketazine will occur to hydrolyze generation hydrazine hydrate and acetone, and the boiling point of hydrazine hydrate whole material system mid-boiling point compared with
Height, belong to heavy constituent, will enter in still-process in tower reactor and be discharged together with sodium chloride brine, distillation will so be greatly reduced
During yield, as the Chinese invention patent of Application No. 201310628958.0 discloses a kind of processing ketazine legal system hydration
The method of hydrazine high-salt wastewater, acetone is passed through into high-salt wastewater, and the hydrazine hydrate in effluent brine is converted into ketazine.This method permits
Perhaps a certain amount of hydrazine hydrate is present in the by-product salt solution of tower reactor, adds acetone recovery to by-product salt water stripper in subsequent process
Ketazine, therefore processing step is not only increased, and more acetone are added into system, acetone can excessively be led in system
The generation of ketazine back reaction in hydrolytic process is caused, reduces hydrazine hydrate yield.
Therefore, how by control the amount of hydrazine hydrate in tower reactor by-product salt solution improve the yield of ketazine turn into key,
And the addition form of acetone, acetone addition, acetone are different in the coal addition position of destilling tower and the temperature of reaction solution so that distillation
During ketazine yield it is different, while the hydrazine hydrate content brought into by-product salt solution also can be different.
The content of the invention
The purpose of the present invention is to provide ketone in a kind of raising ketazine process hydrazine hydrate still-process to solve the above problems
The method of azine yield, the hydrazine hydrate generated in still-process is reclaimed using this method, tower reactor hydrazine hydrate content is reduced, improves
The yield of ketazine in still-process, so as to further improve the yield of preparation of hydrazine hydrate by use of ketazine, and prevent hydrazine hydrate from entering
Increase subsequent treatment difficulty in by-product salt solution.
Ketazine hydrolysis generation hydration hydrazine reaction is reversible reaction, and hydrazine hydrate is easy to react raw ketazine with acetone, but
In whole destilling tower, acetone is uprising gas, and hydrazine hydrate is dropping liq, and the hydrazine hydrate after hydrolysis generation is had no chance and third
Ketone contacts and generates ketazine, eventually enters into discharge in salt solution and loses.In order to improve ketazine yield, prevent ketazine from hydrolyzing
The hydrazine hydrate generated afterwards, which enters, increases subsequent treatment difficulty in by-product salt solution, devise following technical scheme：
A kind of method for improving ketazine yield in ketazine process hydrazine hydrate still-process, comprises the following steps：
(1) after the reaction solution of synthetic reaction during ketazine process hydrazine hydrate production is handled by heat exchanger and destilling tower
By-product salt solution heat exchange after be sent into destilling tower, after heat exchange reacting liquid temperature be 90-110 DEG C；
(2) gas phase acetone is passed through between 5-15 blocks column plate under input of column plate, the gas phase acetone and reaction solution
Volume ratio is 0.2-0.4, and hydrazine reaction generation ketazine is hydrated in gas phase acetone and reaction solution, reacts the light component ketazine of generation
And excessive acetone is separated by distilling from liquid, through recovered overhead.
Period, following reaction occurs：
N2H4·H2O+2CH3COCH3→(CH3)2C=N-N=C (CH3)2+3H2O
Wherein, the ketone in acetone excessive in step (2) reaction solution and reaction generate ketazine and reaction solution connects
Nitrogen, acetone, ammonia are separated by distilling from liquid, and ketazine process hydrazine hydrate production system is sent back to after recovered overhead
In, acetone, ammonia use as ketazine process hydrazine hydrate production raw material, and ketazine goes hydrolysis to obtain hydrazine hydrate.
The present invention has done following experiment to synthesis reaction solution ketazine yield：
Table 1 is influence of the reacting liquid temperature to ketazine yield, as shown in Table 1, when reacting liquid temperature is 70 DEG C, by-product salt
Hydrazine hydrate content is 5g/L in water, and ketazine yield is relatively low；When reacting liquid temperature is 90-110 DEG C, hydrazine hydrate contains in by-product salt solution
Amount significantly reduces, ketazine high income.
Influence of the reacting liquid temperature of table 1 to ketazine yield
| Sequence number | Reacting liquid temperature (DEG C) | Total hydrazine content (g/L) in by-product salt solution | Yield (%) |
| 1 | 70 | 5 | 84 |
| 2 | 90 | 1.6 | 94.8 |
| 3 | 100 | 1.7 | 94.5 |
| 4 | 110 | 2.2 | 93 |
Table 2 be acetone with reacting influence of the liquid proportional to ketazine yield, as shown in Table 2, gas phase acetone addition with it is anti-
When answering the volume ratio of liquid to be less than 0.2, ketazine yield is decreased obviously, and the volume ratio of gas phase acetone addition and reaction solution is 0.1
When, hydrazine hydrate content is 7g/L in by-product salt solution, and ketazine yield is 78.1%, when gas phase acetone addition and the body of reaction solution
When product is than being more than 0.4, yield improves, but increases the difficulty of subsequent recovery acetone, and acetone recovery will thoroughly not influence ketazine water
The efficiency of solution.
The acetone of table 2 and influence of the reaction liquid proportional to ketazine yield
| Sequence number | Acetone and reaction liquid proportional | Total hydrazine content (g/L) in by-product salt solution | Yield (%) |
| 1 | 0.1 | 7 | 78.1 |
| 2 | 0.2 | 1.5 | 95.2 |
| 3 | 0.3 | 1.6 | 95.8 |
| 4 | 0.4 | 1.58 | 95.8 |
| 5 | 0.5 | 1.42 | 95.5 |
Table 3 is that acetone is passed through influence of the distillation tower position to ketazine yield, it is assumed that reaction solution feedboard is located at n-th layer tower
Plate, as shown in Table 3, hydrazine hydrate content is relatively low in by-product salt solution when being passed through gas phase acetone between 5-15 blocks column plate under feedboard,
Ketazine yield is preferable；Acetone be passed through position under feedboard it is more than 5 blocks of column plates when, it is past because lower tray is more, and also
Lower temperature is higher, ketazine more facile hydrolysis generation hydrazine hydrate, and this partially hydrated hydrazine can not be recovered, therefore hydrazine hydrate yield
It is relatively low；Because the hydrazine hydrate of ketazine hydrolysis generation is largely present, it is necessary to be passed through more gas under 15 blocks of column plates under feedboard
Phase acetone can just make hydration hydrazine reaction generate ketazine, add the load of destilling tower, while to follow-up acetone recovery system band
Carry out larger pressure.
Often rise 1g/L by calculating hydrazine hydrate content in destilling tower tower reactor by-product salt solution, the receipts of ketazine in still-process
Rate will decline 4-5%.Therefore the inventive method is by reducing the content of hydrazine hydrate in tower reactor by-product salt solution, to improve still-process
The yield of middle ketazine, and then improve the yield of hydrazine hydrate in production process.
The acetone of table 3 is passed through influence of the position destilling tower to ketazine yield
| Sequence number | Vapour phase acetone enters the number of plates | Total hydrazine content (g/L) in by-product salt solution | Yield (%) |
| 1 | n-4 | 4 | 87.2 |
| 2 | n-5 | 2.9 | 91.3 |
| 3 | n-8 | 1.51 | 95.2 |
| 4 | n-11 | 1.45 | 95.4 |
| 5 | n-15 | 1.42 | 95.5 |
The beneficial effects of the invention are as follows：The present invention is reversible reaction using ketazine hydrolysis generation hydration hydrazine reaction, is being steamed
Evaporate and gas phase acetone is passed through in tower, the higher hydrazine hydrate of the boiling point in destilling tower is reacted the relatively low ketazine of generation boiling point with acetone
Separated from liquid through recovered overhead, reduce tower reactor hydrazine hydrate content, avoid the hydrazine hydrate of generation from draining with by-product salt solution,
So as to improve ketazine yield, and then improve hydrazine hydrate yield；Reacting liquid temperature is 90-110 DEG C, is passed through the position of gas phase acetone
Between 5-15 block column plates under input of column plate, the volume ratio of gas phase acetone and reaction solution is when being 0.2-0.4, and ketazine is received
Rate reaches more than 95%, and hydrazine hydrate content is less than 1.5g/L in by-product salt solution, reduces the follow-up intractability of by-product salt solution, subtracts
Consumption of the by-product salt solution to treatment agent is lacked.
Brief description of the drawings
Fig. 1 is the process flow diagram of the present invention.
In figure mark for：1- acetone pipe 2- acetone vaporizer 3- gas phase acetone pipe 4- destilling tower 5- destilling tower gas phase pipes 6- steams
Evaporate tower and turn expects pipe 7- input of column pipe 8- heat exchangers 9- synthesis liquid pipe 10- by-product Brine Pipes.
Embodiment
The present invention is further described with reference to the accompanying drawings and examples：
The conventional steps that ketazine process prepares hydrazine hydrate are, by sodium hypochlorite, acetone, ammonia carry out reaction generation ketazine,
Sodium chloride, water, synthetic reaction formula are：
2CH3COCH3+2NH3+NaClO→(CH3)2C=N-N=(CH3)2C+3H2O+NaCl
Ketazine hydrolyzes to obtain hydrazine hydrate, and reaction equation is：
(CH3)2C=N-N=C (CH3)2+3H2O→N2H4·H2O+2CH3COCH3
The reaction solution chemical composition of synthetic reaction for being sent into destilling tower is：
Ketazine, acetone, ammonia, sodium chloride, hydrazine hydrate.
As shown in Figure 1, the reaction solution of synthetic reaction during ketazine process hydrazine hydrate production is sent by synthesizing liquid pipe 9
Enter heat exchanger 8 and after destilling tower turns the by-product salt solution heat exchange that expects pipe 6 comes out, destilling tower 4 is entered by input of column pipe 7, third
Ketone is sent into after acetone vaporizer 2 gasifies by acetone pipe 1 and is passed into destilling tower 4, gas phase acetone and reaction by gas phase acetone pipe 3
Hydrazine reaction generation ketazine is hydrated in liquid, the ketone in reaction solution in excessive acetone and the ketazine and reaction solution of reaction generation connects
Nitrogen, acetone, ammonia are separated by distilling from liquid, send back to ketazine process water after the recovery of tower top destilling tower gas phase pipe 5
Close in hydrazine production system, and the by-product salt solution after heat exchange is sent to subsequent treatment process by by-product Brine Pipe 10.
The yield of ketazine in the embodiment of the present invention of table 4
Embodiment 1：
(1) after the reaction solution of synthetic reaction during ketazine process hydrazine hydrate production is handled by heat exchanger and destilling tower
By-product salt solution heat exchange after be sent into destilling tower, according to flow control heat exchange after reacting liquid temperature be 90 DEG C；
(2) gas phase acetone is passed through at the 5th block of column plate under input of column plate, the gas phase acetone being passed through is 4L, instead
It is 20L to answer liquid, is hydrated hydrazine reaction generation ketazine in gas phase acetone and reaction solution, excessive acetone and reaction generation in reaction solution
Ketazine and reaction solution in ketazine, acetone, ammonia separated by distilling from liquid, send back to after recovered overhead
In ketazine process hydrazine hydrate production system, acetone, ammonia use as ketazine process hydrazine hydrate production raw material；Ketazine goes to hydrolyze
To hydrazine hydrate.
As shown in table 4, hydrazine hydrate content is 0.82g/L in by-product salt solution after testing, and ketazine yield is up to 98.24%.
Embodiment 2：
(1) after the reaction solution of synthetic reaction during ketazine process hydrazine hydrate production is handled by heat exchanger and destilling tower
By-product salt solution heat exchange after be sent into destilling tower, according to flow control heat exchange after reacting liquid temperature be 110 DEG C；
(2) gas phase acetone is passed through at the 15th block of column plate under input of column plate, the gas phase acetone being passed through is 8L, instead
The volume for answering liquid is 20L, is hydrated hydrazine reaction generation ketazine in gas phase acetone and reaction solution, excessive acetone and anti-in reaction solution
Ketazine, acetone, ammonia in the ketazine and reaction solution that should generate are separated by distilling from liquid, after recovered overhead
Send back in ketazine process hydrazine hydrate production system, acetone, ammonia use as ketazine process hydrazine hydrate production raw material；Ketazine is gone
Hydrolysis obtains hydrazine hydrate.
As shown in table 4, hydrazine hydrate content is 0.95g/L in by-product salt solution after testing, and ketazine yield is up to 96.33%.
Embodiment 3：
(1) after the reaction solution of synthetic reaction during ketazine process hydrazine hydrate production is handled by heat exchanger and destilling tower
By-product salt solution heat exchange after be sent into destilling tower, according to flow control heat exchange after reacting liquid temperature be 100 DEG C；
(2) gas phase acetone is passed through at the 11st block of column plate under input of column plate, the gas phase acetone being passed through is 6L, instead
The volume for answering liquid is 20L, is hydrated hydrazine reaction generation ketazine in gas phase acetone and reaction solution, excessive acetone and anti-in reaction solution
Ketazine, acetone, ammonia in the ketazine and reaction solution that should generate are separated by distilling from liquid, after recovered overhead
Send back in ketazine process hydrazine hydrate production system, acetone, ammonia use as ketazine process hydrazine hydrate production raw material；Ketazine is gone
Hydrolysis obtains hydrazine hydrate.
As shown in table 4, hydrazine hydrate content is 0.90g/L in by-product salt solution after testing, and ketazine yield is up to 97.65%.
Claims (2)
- A kind of 1. method for improving ketazine yield in ketazine process hydrazine hydrate still-process, it is characterised in that including following step Suddenly：(1) reaction solution of synthetic reaction during ketazine process hydrazine hydrate production is passed through into the pair after heat exchanger and destilling tower processing Destilling tower is sent into after production salt solution heat exchange, reacting liquid temperature is 90-110 DEG C after heat exchange；(2) gas phase acetone, the volume of the gas phase acetone and reaction solution are passed through between 5-15 blocks column plate under input of column plate Than being hydrated hydrazine reaction generation ketazine for 0.2-0.4, in gas phase acetone and reaction solution, the light component ketazine and mistake of generation are reacted The acetone of amount is separated by distilling from liquid, through recovered overhead.
- 2. a kind of method for improving ketazine yield in ketazine process hydrazine hydrate still-process according to claim 1, its It is characterised by：In step (2) reaction solution excessive acetone and reaction generation ketazine and reaction solution in ketazine, third Ketone, ammonia are separated by distilling from liquid, are sent back to after recovered overhead in ketazine process hydrazine hydrate production system, third Ketone, ammonia use as ketazine process hydrazine hydrate production raw material, and ketazine goes hydrolysis to obtain hydrazine hydrate.
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| EP3263627B1 (en) * | 2016-06-28 | 2020-08-12 | Covestro Deutschland AG | Distillative separation of ketazin from polyurethane dispersions |
| CN112179967A (en) * | 2020-09-30 | 2021-01-05 | 宜宾海丰和锐有限公司 | Online detection method for hydrazine hydrate in production process of ketazine process hydrazine hydrate |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1792825A (en) * | 2005-11-22 | 2006-06-28 | 宜宾天原股份有限公司 | Process for treating hydrazine hydrate waste salt water by ketone linking nitrogen method |
| CN101311107A (en) * | 2007-05-21 | 2008-11-26 | 华东理工大学 | Method for gas stripping and separating hydrazine from hydrazine-containing solution using acetone and use thereof |
| CN102153056A (en) * | 2011-02-15 | 2011-08-17 | 杭州海虹精细化工有限公司 | Technology for continuously producing hydrazine hydrate |
| CN103613237A (en) * | 2013-11-28 | 2014-03-05 | 天津普莱化工技术有限公司 | Technique for processing high-salinity wastewater in preparation of hydrazine hydrate by use of ketazine process |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1792825A (en) * | 2005-11-22 | 2006-06-28 | 宜宾天原股份有限公司 | Process for treating hydrazine hydrate waste salt water by ketone linking nitrogen method |
| CN101311107A (en) * | 2007-05-21 | 2008-11-26 | 华东理工大学 | Method for gas stripping and separating hydrazine from hydrazine-containing solution using acetone and use thereof |
| CN102153056A (en) * | 2011-02-15 | 2011-08-17 | 杭州海虹精细化工有限公司 | Technology for continuously producing hydrazine hydrate |
| CN103613237A (en) * | 2013-11-28 | 2014-03-05 | 天津普莱化工技术有限公司 | Technique for processing high-salinity wastewater in preparation of hydrazine hydrate by use of ketazine process |
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